1. Field of the Invention
This invention relates to an electrical digital signage system, and in particular, it relates to an electrical digital signage system which employs a Category 5 (Cat. 5) differential cable to achieve bi-directional transmission of video data signals.
2. Description of the Related Art
Electrical digital signage or billboards can conveniently and timely dispatch information. In recent years, with the advance of relevant technologies, digital signage has gained widespread use, and can now be seen at places such as airport waiting areas, box offices at cinemas, stores, malls, public transportation areas, etc. Digital signage devices are often located at places where consumers may stop temporarily, and use audiovisual effects to attract their attention. Thus, digital signage has a large commercial potential. The timeliness of the content, the ability to interact with consumers, and the stability of the system are important properties of advertising system for advertisers and manufacturers. Due to these properties and the audiovisual abilities, digital signage has many advantages in these respects over traditional signage systems. For example, during holiday seasons, promotional information can be timely transmitted to various places of commercial activity via networks, and the signage devices at these places of commercial activities can immediately update the information displayed on the signage. Such mode of advertising will likely gain wider use in the future. In addition, digital signage is environmentally friendly as it replaces conventional signage made of paper of other materials.
A system that provides for central management of multiple digital signage devices will further allow convenient content management. In particular, digital signage devices that are coupled to networks via wireless communication allow contents to be easily updated without physically replacing the signage. Such intelligent digital signage system will be used more widely in the future.
While current digital signage systems can already achieve many advantageous functions, many current digital signage systems are set up to be uni-directional (i.e., data can be transmitted from a management device to the signage devices for display, but data transmission only goes in one direction) and non-IP enabled. Many systems are set up in different ways depending on whether they are centrally managed or separately managed. After a digital signage system is set up, if it is desired to be upgraded to a bi-directional data transmission system, the entire network system may need to be re-built or additional transmission lines may need to be added. This is inconvenient and costly.